The structure, expression, and evolution of crystallin genes of vertebrates and invertebrates are being studied. The four functional promoter elements described in the alphaA-crystalline gene of the mouse (DE1, alphaA-CRYBP1, PE1, and PE2) and five in that of the chicken (DE3, DE2A, DE2B, DE1A, and DE1B) are surprisingly different, considering the gene is orthologous in these species with the same high-level expression in the lens. We have cloned putative trans-acting factors which bind to the mouse alphaA-CRYBP1 and chicken DE2A sites. The alphaA-CRYBP1 gene has been cloned and characterized; cDNA analyses indicate that it produces alternatively spliced mRNAs. The alphaA-CRYBP1 protein also appears to be cleaved in a tissue-specific fashion. The mouse DE1 site appears to bind a member of the CREB/ATF family. Four functional elements (alphaBE-1, alphaBE-2, alphaBE-3, and MRF) have been identified in the mouse alphaB-crystallin enhancer, alphaBE1, alphaBE-2, and alphaBE-3 are used in muscle and lens, while MRF binds myoD and myogenin and is muscle specific. We have identified in the chicken betaA3/A1- crystallin gene an enhancer containing an AP-1 consensus-binding sequence which increases lens transcription but is not necessary for lens specificity. Transfection and gel mobility shift experiments indicate that the PL-1 and PL-2 functional elements of the chicken betaB1- crystallin promoter and the AP-1/ARE sequence of two squid crystallin promoters are necessary for activity in transfected chicken lens cells and bind similar nuclear proteins of the chicken lens. Six chicken nuclear proteins that bind to the PL-1 sequence have been cloned. Transgenic mouse experiments indicate that the delta2-crystallin enhancer works efficiently in the lens and also has modest activity in the cornea, brain, and retina. Squid glutathione S-transferase (GST) and two squid S-crystallin cDNAs have been expressed; GST is very active while the S- crystallins show little if any activity. Cephalopod cDNAs for omega- crystallin/ALDH, immediate filament protein, and alpha- and beta-tubulin have been cloned; the genes for all but alpha-tubulin were lens specific. Cloned cubomedusan jellyfish J3-crystallin has been shown to be a novel protein.